1. Field of the Invention
The present invention relates to a glass polishing system, and more particularly to a glass polishing system for polishing one surface of a glass used in a liquid crystal display.
2. Description of the Related Art
Generally, it is very important that a glass (or, a glass pane) applied to a liquid crystal display keeps its flatness to a certain level so as to accurately realize images. Thus, fine waviness existing on a surface of a float glass formed through a float chamber should be removed.
Such a glass polishing process may be classified into so-called ‘Oscar’ type polishing in which glasses are individually polished one by one, and so-called ‘inline’ type polishing in which a series of glasses are successively polished. Also, the glass polishing process may be classified into ‘single side polishing’ in which only one surface of a glass is polished, and ‘double side polishing’ in which both surfaces of a glass are polished.
In a conventional glass polishing device, while a polishing plate (or, a top board) having a polishing pad installed thereto is moved in a horizontal direction and a polishing stage (or, a bottom board) having a glass located thereon is rotated, the glass is polished using a polishing slurry freely falling down onto the polishing plate.
However, in the conventional polishing process, a certain pressure is formed between the glass and the polishing plate. In this reason, the polishing slurry cannot sufficiently permeate through grooves formed in the polishing plate, so it is not easy to stably and uniformly supply the polishing slurry. In addition, in the conventional polishing device, while being supplied, the polishing slurry may unnecessarily flow down out of the polishing plate, which makes it difficult to uniformly polish the glass.
Meanwhile, the conventional glass polishing device gives a force to a glass due to the weight of the top board, or the polishing plate, itself, so it is impossible to apply uniform force to the glass over the entire area of the polishing plate. Thus, a finally polished glass has irregular flatness at every region of the rectangular glass, which results in many defective products. In particular, this problem becomes more serious as a size of the polishing plate is increased (e.g., about 1,000 mm in diameter) due to the increase of a size of a liquid crystal display. In detail, in the conventional glass polishing device, the polishing plate contacting with a glass is substantially not able to give uniform force to the glass at every region, and the force applied to the glass is decreased as being distanced from a spindle to which the polishing plate is installed, so uniform polishing is impossible.
In addition, as the polishing plate has a larger size, the maintenance or exchange of the polishing pad attached to the polishing plate of the conventional polishing device becomes more difficult, needs more equipment and consumes more time.